This invention relates generally to hand-held pneumatic rotary drive devices, and more particularly to a device of this class for driving a grinding wheel, useful as a die grinder.
Reference may be made to U.S. Pat. No. 5,535,646 issued Jul. 16, 1996 showing in FIG. 9 thereof a hand-held pneumatic rotary drive device generally of the same class as the present invention, albeit for use with a bidirectional ratchet drive for a tool.
Hand-held pneumatic rotary drive devices of the type with which this invention is concerned have a pneumatic motor for effecting driving of the instrumentality to be driven thereby, supplied with compressed air via an air hose. Flexibility of the hose permits the manipulation of the device by hand to do the work intended. This invention is especially concerned with the pneumatic circuitry involved, and more particularly with problems which have been encountered in the exhausting of air from prior devices, such as the problem of exhaust air blowing in the user""s eyes (often with particles of debris in the air), exhaust air blowing up the user""s sleeve, and the problem of excessive noise.
Among the several objects of the invention may be noted the provision of a hand-held pneumatic rotary drive device with an air exhaust system such as generally to reduce or to eliminate the above-mentioned problems; the provision of such a device having means for effecting directional adjustment of the exhaust to suit different hand-held positions of the device; the provision of such a device wherein said means is compatible with a connector for a flexible hose for supplying compressed air to the device, the connector allowing swivelling of the device relative thereto; and the provision of such a device with such means which is of relatively simple and economical construction and which enables simple adjustment to select a workable direction for the exhaust.
In general, a hand-held pneumatic rotary device of this invention comprises a generally elongate housing sized and shaped to be held in the hand having a forward end and a rearward end as so held and having an axis extending longitudinally endwise thereof, and having a chamber adjacent its forward end and a pneumatic motor having a rotor rotary in said chamber on said axis, a drive shaft driven by the rotor extending out of said forward end of the housing. The housing has an inlet passage for pressurized air at its said rearward end thereof extending in generally longitudinal direction relative to said housing. An air hose connector is rotary in sealed relation to said housing on an axis extending in generally longitudinal direction relative to said housing, said connector being of tubular form having a bore for flow of pressurized air to said inlet passage, said connector being for connection of an air hose for supplying pressurized air from a source thereof to the bore of said connector and allowing swivelling of the housing relative to the hose and connector. The housing has air delivery passaging for flow of pressurized air from said inlet passage to the motor, said delivery passaging having a valve therein, and said housing has a member thereon operable by the hand holding the device for operating the valve. The housing has air exhaust passaging therein for exhausting air from the motor chamber extending from the chamber to an outlet at said rearward end of the housing located laterally outward of said connector, and an air deflector for exhaust air exiting said exhaust passaging outlet rotatable around said connector for deflecting exhaust air laterally outward in selected direction away from the user holding the device.
Other objects and features will be in part apparent and in part pointed out hereinafter.